Your guide to wireless tech for the internet of things

Of the 3.5 billion cellular IoT connections forecast for 2023, North East Asia is expected to account for 2.2 billion of them, driven in large part by China. Chart courtesy of Ericsson.

This week saw several deep dives into the current state of wireless for IoT. Basically wireless is set to edge out wired connectivity to account for 55% of communications chip shipments in 2018, according to a report by IHS Markit. That’s actually down a bit from the previous year, when 60% of the communications chips sold were for wireless tech. But the overall market for communications chips is rising as more and more devices need to talk to the internet or to each other.

This is only the beginning. The IHS report highlights five wireless technologies to watch; they are Wi-Fi (802.11ax), NB-IoT and LTE Cat M1, Bluetooth Mesh, LoRa, and 5G. I’ve covered all of these at various points in my tenure, but here’s a quick rundown of where they will win out and what they offer.

Bluetooth Mesh: This relatively new wireless tech is good for both consumer and industrial settings because it takes the ubiquity of Bluetooth (it’s on handsets everywhere) and gives it mesh capabilities to extend wireless range. That means customers can use Bluetooth devices to create a network that’s more resilient and can transfer data even when you want to talk to a device that’s more than 20 or 30 feet away. It’s also excellent for battery-powered devices since Bluetooth uses less power than Wi-Fi or cellular technologies. Startups are using Bluetooth Mesh for wayfinding, advertising, location tracking, and other new use cases, especially when they want to communicate with consumers using their mobile phones. You’ll see it in light bulbs, light switches, medical settings, and retail stores. You won’t see it when you need to transfer large amounts of data such as videos or imaging files because Bluetooth throughput is lower than other wireless technologies.

Wi-Fi (802.11ax): We all are familiar with Wi-Fi; Wi-Fi (802.11ax) is merely its latest iteration. It offers incredibly fast data rates and a technology that helps manage the way information is transferred over different Wi-Fi channels in an environment with lots of devices all talking at the same time. Without technology to manage multiple devices and help them share the spectrum, packets from a video stream might get delayed while packets for a sensor pass through. There are also other elements to this technology that help lower power consumption and boost capacity using multiple antennas. Basically Wi-Fi under this standard is really fast and a lot smarter than it used to be. Smarts are good when the network is handling dozens of devices.

In general, no matter what version of Wi-Fi you’re talking about, the tech will work for devices that require a lot of data. Think video and fat image files. But Wi-Fi is terrible for sensors because it sucks battery life and also isn’t great at reaching out-of-the way locations, where sensors are often placed. There is also a challenge in the form of many connected devices coming on the market with old Wi-Fi modules that can’t handle the strains of today’s networks. You will find Wi-Fi in everything from consumer homes to industrial environments. You won’t find it in places without power or a reliable broadband connection, such as mining camps, farmers’ fields etc.

NB-IoT and LTE Cat M1: These are two cellular standards for sending relatively small amounts of data over cellular networks. They are part of a class of wireless technologies that can create Low-Power Wide-Area Networks (LPWANs). NB-IoT has crazy low data rates (as in, you can only send 250 kilobits per second) while its cellular cousin, LTE Cat M1, sends a bit more data at 1 Mbps. While they are often lumped together, LTE Cat M1 is closer in nature to the cellular data we know and love, and cellular operators can deploy it quickly over their existing LTE networks. NB-IoT requires a bit more maneuvering at the cell tower, including equipment and software upgrades. It’s not a giant leap, but it’s a bit more work.

Because these are cellular technologies they can provide coverage over wide areas, ensure the security of the communications network, and make sure there’s someone you can call when network problems arise, all while consuming less energy than Wi-Fi or traditional cellular. However, the modules are still expensive (carriers are working with chipmakers to get to a $5 price point for modules) and working with a carrier to get good pricing can be a challenge. You’ll see shipping companies, fleet management companies, and any industry tracking global or nationwide shipments of high-value items use NB-IoT and LTE Cat M1. Medicine is also going to use these and other LTE technologies for certain FDA-approved devices, especially those that go home with patients. You’ll also see the carriers support in-home security sensors using NB-IoT, especially in Europe.

Europe and Asia are the leaders right now in NB-IoT, while the U.S. carriers have focused first on deploying LTE Cat M1.

LoRa: If cellular LPWANs seems too expensive, Wi-Fi too battery-intensive, and Bluetooth Mesh too local, then LoRa is the tech for you. LoRa networks can transmit a little bit of a data a long way. How much data they can send depends on how they are tuned for power consumption and distance, but it’s roughly 25 kbps or even less. While LoRa is an open standard, only one chip vendor (Semtech) makes the radios, so some companies are reluctant to rely on a network where all devices on that network will need a product from a single vendor.

LoRa networks also require gateway devices and someone to manage the network. That’s why we see companies such as Comcast and even carriers creating LoRa-based networks for clients. The technology is generally better for devices that don’t need to ping the network more than a few times a day, so it’s less than ideal for tracking frequently used objects, and will likely be used on private campuses. You’ll see LoRa used in warehouses, campuses, and possibly on farms for getting reads from sensors or devices that need to check in.

5G: IHS put this in its report, and I am a little frustrated by the idea simply because 5G can be a variety of things. In a fixed-mobile setting, 5G can provide super-fast broadband for homes and apartments in urban and suburban areas. In a factory setting, it can deliver incredibly low latency, which could convince some manufacturing firms to use it in automated processes instead of wired tech. And in the cellular world, it has the potential to deliver enough bandwidth to enable autonomous driving. So while 5G is an exciting tech to watch, it’s tough to say yet where it will find the first and best use cases for IoT.

There are dozens of other wireless technologies that the IoT uses today. Some will loose market share over time. For example, ZigBee and Z-Wave, will likely see Bluetooth Mesh take on some of the roles those technologies played. But they will still be around in the next five to seven years. Other technologies, such as the proprietary LPWANs like Sigfox and Ingenu, will likely see their market share taken by LoRa and cellular.

For me, the larger question in IoT wireless will be how far cellular can go compared with technologies that use unlicensed spectrum, such as Wi-Fi, Bluetooth, and even LoRa. I don’t think cellular will ever go away, but carriers will need to adapt their business models and pricing for an era of billions of connected devices, even ones that don’t have a high value, if they want to gain on technologies like Wi-Fi. What’s more likely is that carriers will continue to find the high-value devices and services to justify their pricing and the high cost of modules, all while unlicensed technologies get more and more clever about creating good-enough networks for the majority of connected devices to use.